Advertisements on television and in newspapers consistently hype the latest diet fads. News reports comment on the latest research about the negative effects of obesity on Americans.
The President's Council on Physical Fitness and Sports promotes the healthy effects of exercise. Yet, even with these and other efforts, the rate of increase in overweight and obese Americans continues to climb. According to University of Missouri-Columbia biomedical researchers Frank Booth and Simon Lees, every U.S. child and adult will be obese by 2044 and 2058, respectively, if the current progressive rise continues.
"If all the work we are doing to promote physical fitness is working, than why does the problem continue to get worse," said Booth, who gave the Joseph B. Wolffe Memorial Lecture at the American College of Sports Medicine's annual conference today. "We have increased sedentary activities for children by 4.5 times since 1950. Children and adolescents now spend 45 hours each week watching television, working on the computer, playing video games or watching movies.
In his lecture, Booth cited statistics that demonstrated a three- to fourfold increase in the percentage of overweight U.S. children and adolescents since the mid-1980s. Booth believes the increase in obesity is due to an incompatibility between human genes and societal pressures. Human genes evolved to support a great deal of physical activity, yet in the last 20 years, physical activity has decreased dramatically in the United States, Booth said.
In a recent study using rats, Booth found that a 48-hour period of inactivity can lead to a large increase in the amount of fat and the size of fat cells in the body. In a similar study, Booth found that insulin sensitivity decreases when a body is inactive for two days. This decreased insulin efficiency may be a precursor to diabetes and other related diseases. Both studies were published in The Journal of Physiology.
According to Booth, other problems associated with inactivity include: